Impact of pulmonary and extrapulmonary tuberculosis infection in kidney transplantation: A nationwide population-based study in Taiwan

Background: Tuberculosis (TB) has been reported to increase morbidity after kidney transplantation and pose a therapeutic challenge. However, population-based research, specifically focused on the association between kidney transplantation and subsequent pulmonary or extrapulmonary TB, is lacking. Methods: A nationwide population-based study was conducted using Taiwan's National Health Insurance Research Database, which provided claims data belonging to kidney transplant recipients during 1997-2006. Multivariate analysis was used to identify independent risk factors for TB after kidney transplantation. Kaplan-Meier survival analysis was used to assess the outcome of patients with TB. Results: Among 4554 kidney transplant recipients over the 10-year period, 109 (2.4%) patients with newly diagnosed TB were identified: 75 patients with only pulmonary involvement, and 34 with extrapulmonary spread. The incidence of kidney transplant recipients developing TB was 638 per 100,000 person-years. The independent risk factors for post-transplant TB included cyclosporine-based immunosuppressant agents during the first year after kidney transplantation (odds ratio [OR]: 1.98, P = 0.001), hepatitis C infection (OR: 1.79, P = 0.024), and chronic obstructive pulmonary disease (OR: 1.50, P = 0.041). Kidney transplant recipients who developed TB had a lower 5-year survival rate than those who did not (78.6% vs. 93.4%, P = 0.001). Conclusions: Kidney transplant recipients in Taiwan did have a high risk of TB infection, with high proportion of extrapulmonary spread. Physicians need to be vigilant in surveying for TB in kidney transplantation, especially in high-risk patients.